Safety stop



Nov. 9 1926. 1,606,542

c. H. Usl-1ER SAFETY sTP Filed MarchY 28, 1924 INVENTOR BMW/f ATTORNEYSPatented Nov. 9, 1926.

UNITED rSTATES PATENT OFFICE.

CHARLES H. 'USI-IER, OF CHICOPEE FALLS, MASSACHUSETTS, ASSIGNOR TO LAMBKNITTING- MACHINE COMPANY, A CORPORATION 0F MASSACHUSETTS.

SAFETY STOP.

Application filed March 28, 1924. Serial No. 702,684.

This invention relates to a stop device for machines generally. Itsobject is to provide an improved unitary stop device for attachment toalmost any machine having a belt or clutch shifting rod operable tocontrol a clutch or belt to start andstop the machine. By supplying aspring operable to shift said rod when the latter is released by theoperation of the latch of my device the machine may be stopped.

The broad idea of releasing a spring pressed rod to shift a clutch orbelt is very old. My improvement is in the particular mechanism Iprovide for the purpose.

I preferably use an electrically operated door lock of standardconstruction which may .be bought in hardware stores. This I combine ina frame with a simple lever pivoted in the frame. The lock acts as alatch on the lever and the lever is adapted to act as a latch on thespring pressed rod of the machine. The said frame is arranged toposition the lever with respect to the rod. whereby the lever may workon the rod.

The frame with the lock and lever wholly supported therein constitutes aunit for convenient attachment to any machine. The specific structureherein disclosed has been applied to a knitting machine.

The structure constituting my invention is shown in the drawings, inwhich:

- Fig. 1 is a side elevational view of the device; and

Fig. 2 is a view taken on the line 2--2 of Fig. 1.

v The invention will now be described in detail. A frame 1 is provided'7preferably of sheet metal formed into the shape of a U having parallelside walls 2 connected by an upper end wall 3. A standard electric doorlock L interfits the side walls 2 of the frame and is secured thereto bysuitable means such as rivets or screws 4. The door lock may be of anystandard construction but a form that I have found to be adapted for usein connection with my invention will now be described. A latch 5 ispivoted to the lock frame at 6 and carries in its outer end a roller 7.A spring (not shown) is provided within the lock to urge the latchtoward its outer or latched position shown inFig. 1. A keeper 8 movablein the lock is constructed and arranged to lie behind the latch to holdthe same in its latched position, to prevent an accidental depressing ornonlatching movement thereof. Magnets 9 within the lock are provided toactuate the plate or keeper 8 and withdraw the same from engagement withthe latch mechanism whereby the latch is permitted to be depressed, aswill later appear. It will be understood that the latch is normallyspring pressed outwardly to a latched position and held therein by akeeper and that the magnets are cmployed to withdraw the latch keeper,to permit the latch to be depressed by any pressing action that may beapplied to the roller of the latch. The operating details of the latchdevice 5 are all well known and may be found in standard electric doorlock constructions as sold in most hardware stores.

A, lever member 10 which functions as a lock upon the shifter rod R ispivoted to the frame at 11 and is provided with a latch engaging notch12 and a circular latch depressing surface 13 best shown in Fig. 1. Thelever 10 is adapted to be swung by the rod R in a counter-clockwisedirection from its rod latching position, shown in Fig. 1, tonon-latching positions, as will later be described.

A reciprocating` rod R is shown that may represent a belt or clutchshifting rod of any machine and that may be guided in a guideway 14:fixed to a frame 15 or other part of the machine.

A collar 16 is fixed to the rod R and a coil spring 17 is interposedbetween the collar and bearing guideway 14 that tends to move the rod tothe left and hold the belt or clutch shifter in a non-operating positionwhen released by the stop device.

. In connection with the embodiment .of the invention shown, it will beassumed that the rod is moved to the right against the action of thespring 17 to operate a clutch or belt shifter for operating the machinewhile a reverse movement to the left will disengagc the drivingmechanism to stop the machine. A collar 18 fixed to the rod R isprovided with a disk or flange 19 that is adapted to engage a notch 2Oprovided in the upper side of the lever 10.

The .frame 1 of the stop device may be conveniently secured to the frame15 of a machine by screws 21 or the like and is so located with respectto the rod R that the collar 19 thereof may engage with the notch 20 ofthe lever 10.

To operate a machine with which my stop device is used, the rod R ismoved by hand to the right and against the action of the spring 17 forengaging the clutch or other driving mechanism. rthe collar 19 of therod automatically engages the notch 2O of the lever 10 and moves thelever in a clockwise direction to the position shown in Fig. 1. Thespring pressed latch 5 moves to a latching position wherein the roll 7is in engagement vvith the notch 12 of the lever and holds the leverfrom a counterclockvvise movement. The operation of shifting the rod ittherefore sets the latch device as the latch 5 and its roll 7 engagesnotch 12. rlhe rod being urged to its non-operating position by thespring 17 is held in anl operating position by means of the collar 1i),4lever 10 and latch 5. By the arrangement shown, the thrust of thespring 17 upon the latch 5 is greatly reduced by reason of the ratio theleverages between 11v and 20 and between 11 and 12. This reductionenables me to usemy simple electrical latch device even lthough thespring 17 is very powerful. The arrangement constitutes one feature ofmy invention.

Magnets 9 of the lock L are preferably connected by suitable meansto-any circuit that may include one ormore dry cells and a circuitcontrolling switch. The circuit switch may take any form such as a pushbutton or other device adapted to open or close the circuit but isusually attached to or controlled by relatively movable parts of themachine itself. That is, the 4circuit control may be so arranged thatthe circuit may be closed by the machine at 'the termination of anynumber Lof-cycles or at any other time depending upon the type ofmachin-e With which the device is used.

' Whenever the circuit is closed ,and the magnets supplied with anelectrical current, the keeper 8 is elevated to permit a depressingmovement Vof the latch. Since `the lever 10 isV at all times 'beingurged in a counter-clockwise direction by its connection with the springpressed rod R- the ,WithdraWal of the keeper permits the lever to movet-o the 'right and to depress the latch 5. As vthe lever 10 swings to'the right the roll of the latch is engaged by the cam surface 13 of thelever which holds the latch in its depressed position. As `the leverswings to the right the collar V19 `of the rod is released by the notch2O and the spring 17 actuates the rod R to the 'left and disengages theclutch lor pulley `driving mechanism controlled thereby. lWhen itisdesired to again operate the machine by a right hand movement ofthe rodthe lever and latch are reset to the latching vposition shown in Fig. 1by the engagement of the collar 19 and notch 20 lof the lever whichmoves frame 10 to the position shown in Fig. l.V

From the foregoing description, it is seen that no matter liovv powerfulthe rod shift` ing spring is, the leverage between the latch of the lockand the latch of the simple lever on .the rod is such ,that almost nopower at all. will release the lever `on the rod.Y In actual practice,a. singleJ dry celll Will Operate the lock to release the lever arm evenagainst a very powerful spring.

l consider that the chief feature of my invention is the extremesimplicity of the means by which supply an eifective electricallyoperated stop device tamachines of all sorts, even though they Vrequireavery powerful spring to shift thestarting rod.

that l claim is: l

1. The combination of a spring pressed shifter rod with a release devicecomprising, a frame, a collar carried by said rod,`a lever pivoted insaid frame having a latch notch and a recess for engagementvivith said collar, a lock carried in said fra-me including an electrically operatedlatch for engaging the notch of said lever, all'adapted and arrangedwhereby the rod is held from a shifting movement by `the lever While thesaid 'lever is held in latc-hed position Iby the latch of the lock.

2. A unitary stop device for application to `machines having springVpressedyshift-ing rods, said device comprising a `U shaped frameadapted to rbe attached to the machine so its ilegs straddle theshifting rod, ,acur-veld lever pivoted Vto :the `frame close Eby ftheshifting rod, an electrically operated latch mechaliism -or lock mountedbetween the llegs of the `frame with its flatch Vlocated -at a` remotepoint from said pivot,said flever being provided With releasable means"to lengage and hold the rod adjacent saidpiv'ot and means engageablelWithsaid'latch remote from said ivot, the surfaces ofsaid curved leve-rbeing designed to cooperate with the rod and latch to automatically setthe stop device from the movement of the rod in one direction and tohold the latch out of operation upon the movement ofthe rod in theopposite direction.

3. A unitary stop device comprising a U shaped frame having anelectricallyoperated door loci; mounted between its flegs vvith thelatch thereof positioned at the outer o pensignature.

' CHARLES H. USI-IER.

